Brunswick Corporation

Bruce A Schroeder

Matthew W Jaeger

Michael A Karls

James M Horak

Christopher J Luckett

Darrin L Doty

George E Brown

Norman W Schweitz

A heat exchanger assembly is provided for a marine propulsion system having a closed loop cooling system. The heat exchanger body encloses a series of tubes carrying sea water which removes heat from the engine coolant. The heat exchanger includes an integrally connected top tank. A single venting orifice is provided into the top tank from the heat exchanger body. A heat exchanger coolant outlet is in direct fluid communication with both a system bypass and the coolant in the top tank. An auxiliary inlet for coolant from the top tank is located in the heat exchanger coolant outlet downstream of the bypass inlet, thereby promoting the ability of the system to draw coolant through the top tank rather than the bypass. The invention minimizes cavitation and reduces the creation of negative pressure at the circulating pump.

Heat exchanger for marine engine cooling system

A sea water pump (130) for a marine propulsion system includes a housing (130) having a generally cylindrical pumping chamber (134) defined by a generally cylindrical sidewall (136) extending axially between opposite end walls (138 and 140). A multi-vaned rotary impeller (44) in the chamber is driven by an impeller shaft (28) extending axially into the chamber through one of the endwalls (40). An intake port (146) at the other endwall (140) has a first branch (148) providing radial flow (170, 172) into the chamber, and a second branch (154) providing axial flow (178) into the chamber. A discharge port (158) has a first branch (160) receiving radial flow (174, 176) out of the chamber, and a second branch (166) receiving axial flow (180) out of the chamber. The housing (132) is an integrally molded one-piece cup-shaped unit including the cylindrical sidewall (136) integral with an end cap (144) providing a flat inner wall wear surface (140) providing the noted endwall engaging an axial end (50) of the impeller in sealing sliding relation.

High capacity simplified sea water pump

A thermostat assembly for a marine engine having a closed loop cooling system provides an additional bypass for engine coolant flow. The assembly includes a housing having an inlet that receives engine coolant, a thermostat outlet that is connected to a heat exchanger, and a bypass outlet that is connected directly to a circulating pump that circulates engine coolant to the engine and bypasses the heat exchanger. A thermostat having a restricting plate is mounted in the thermostat outlet in the housing. The housing includes an internal structural standoff around the bypass outlet. When engine coolant enters the thermostat housing and the thermostat is closed, engine coolant passes between the thermostat restricting plate and the bypass standoff and flows through the bypass outlet directly to the circulating pump. This increases the flow of engine coolant to the engine when the engine is cold. When the engine begins to heat up the thermostat opens, coolant flows through the thermostat opening to a heat exchanger, and the restricting plate moves towards the standoff around the bypass outlet to divert the flow of engine coolant from the bypass outlet to the thermostat outlet. The thermostat restricting plate thereby acts as a shuttle valve directing engine coolant between the bypass outlet and the thermostat outlet.

Thermostat assembly for a marine engine with bypass

A thermostat housing assembly for a marine engine having a first inlet to receive sea water and an outlet that is connected to a circulating pump that circulated cooling water to the engine. A baffle is located in the housing and prevents direct flow between the sea water inlet and the outlet. The housing defines a pair of passages with a first of the passages providing communication between the sea water inlet and forms a first chamber which communicates with a pair of manifold outlets that are connected to the manifold. A second of the passages provides communication between the sea water inlet and the outlet to the circulation pump. The housing also includes a return inlet for returning water from the engine and the return inlet is connected to the second passages. A thermostat is mounted in an opening between the passages and when the thermostat is open a portion of the returning cooling water will be directed through the thermostat opening to the first passage and mixed with incoming sea water and then directed to the manifolds.

Growing community of inventors

Stillwater, OK, United States of America

Bruce A Schroeder